Karisa Terry

Outside Beringia: Why the Northeast Asian Upper Paleolithic Record Does Not Support a Long Standstill Model

After nearly a century searching for evidence of Pleistocene Americans, in the last decade new methods, data, and ideas have brought us closer to reaching a clearer understanding of Native American origins than ever before, but they have also renewed debates about the routes and timing of dispersal. While more researchers have emphasized coastal migration (e.g., Erlandson et al. 2015, 410–411), archaeological evidence for Pleistocene maritime economies remains elusive, and considering current sea levels, Pleistocene archaeological sites along the north Pacific coast may remain hidden for the indefinite future. Concurrent with the archaeological debates, genetic research has radically transformed how we perceive human dispersal to the New World. Overwhelmingly, paleogenomic data point to a northeast Asian origin, and new studies hint at the occurrence of a long incubation period, or standstill (Tamm et al. 2007), in Beringia immediately after dispersal from Asia, but before dispersal to the rest of the Americas. Models suggest this Beringian standstill lasted as long as 15,000 years (Kitchen et al. 2008, 4) or as short as 8000 years (Raghavan et al. 2015, 7), and, accordingly, migrating groups entered Beringia as early as 32,000 cal yr BP (Kitchen et al. 2008, 4; Mulligan and Kitchen 2013, 179), or as recently as 23,000 cal yr BP (Raghavan et al. 2015, 4). There they remained through the Last Glacial Maximum (LGM) and into the early late-glacial periods. During this time, the Beringian populations may have grown to 10,000 individuals (Kitchen et al. 2008, 2), but LGM conditions isolated them until temperatures adequately warmed and ice sheets retreated, about 14,000± 1000 cal yr BP. Beringia is considered the standstill location, with terrestrially adapted Ice-Age humans living in isolation in a refugium or refugia without any gene flow from Asia after initial Beringian colonization (e.g., Hoffecker et al. 2016). Two key problems exist with the Beringian standstill model, both of them relating to patterns in the archaeological record. First, there is a lack of archaeological evidence in Beringia for the incubating population, in other words no clear link between Yana RHS in western Beringia and Swan Point in eastern Beringia, dating to 30,000 and 14,000 cal yr BP, respectively (Holmes 2011, 182; Pitulko et al. 2004, 54) (Figure 1). This 16,000-year gap is explained by suggesting that intervening sites remain undiscovered, with some being submerged below the Bering Sea (Hoffecker et al. 2016, 76). What is more, microblade technology, which has long been considered to represent early humans in Beringia, and is found at some of Beringia’s earliest late-glacial sites (e.g., Swan Point and Diuktai Cave (Holmes 2011, 184–185; Mochanov 1978, 59)), did not emerge until the LGM in northeast Asia (e.g., Kuzmin et al. 2007, 2). If the earliest occupants of Yana RHS at 30,000 cal yr BP, when no microblades have been found, represent a Beringian population that persisted in isolation from the rest of northeast Asia through the late Pleistocene, how can we explain the spread of microblade technology into the region 10,000 years later, after 20,000 cal yr BP? Could the transmission of such a revolutionary projectile technology have occurred without accompanying culture contact and gene flow between mainland Asia and Beringia? These lingering questions continue to perplex us. Correspondence to: Ian Buvit. Email: ian_buvit@nps.gov

Lithics and climate: technological responses to landscape change in Upper Palaeolithic northern Japan

Abstract Studies of human behavioural responses to climate change have begun to address traditional archaeological questions in new ways. Hitherto, most of these studies have focused on western Eurasia, but the question of human response to rapid climatic changes in northern Japan during the Upper Palaeolithic period opens up new perspectives. Combining artefact studies and palaeoenvironmental evidence, Japan provides a case study for how quickly modern humans adapted to new environmental challenges, and how that adaptation can be charted through the lithic technologies employed in different geoclimatic circumstances.

Last Glacial Maximum Human Occupation of the Transbaikal, Siberia

Abstract We analyze the late Pleistocene radiocarbon chronology of the Transbaikal region of Siberia and conclude that humans inhabited the area during parts of the Last Glacial Maximum, but completely abandoned it between 24,800 and 22,800 cal yr BP. Moreover, the distinct contrast between non-microblade producing sites and those with microblades on either side of the radiocarbon gap suggests that the new technology arrived with recolonization.